<!DOCTYPE html>
<head>
  <title>Authentication complete</title>
</head>
<body>
  <p>Authentication is complete. If this does not happen automatically, please
  close the window.
  <script>
    window.opener.postMessage({
      'flutter-web-auth-2': window.location.href
    }, window.location.origin);
    window.close();
  </script>
</body>
